We have measured Rb and Sr concentrations in fluid inclusions of quartz in gold deposits, southwestern Hunan. The Rb|Sr isochron ages of 435±9Ma and 412±33Ma are respectively determined, revealing that gold mineralization in this area took place in the Caledonian period rather than in the Wuling|Xuefeng period as traditionally considered. Sr isotope geochemistry of the hydrothermal fluid indicates that the ore|forming materials are of crust origin, derived largely from the ore|hosting strata rather than from the basic dikes. We have measured Rb and Sr concentrations in fluid inclusions of quartz in gold deposits, southwestern Hunan. The Rb | Sr isochron ages of 435 ± 9Ma and 412 ± 33Ma are respectively determined, revealing that gold mineralization in this area took place in the Caledonian period rather than in the Wuling | Xuefeng period as traditionally considered. Sr isotope geochemistry of the hydrothermal fluid indicates that the ore | forming materials are of crust origin, derived largely from the ore | hosting strata rather than from the basic dikes.